Projection exposure tool for microlithography and method for microlithographic imaging

Abstract

A projection exposure tool for microlithography for imaging mask structures of an image-providing substrate onto a substrate to be structured includes a measuring apparatus configured to determine a relative position of measurement structures disposed on a surface of one of the substrates in relation to one another in at least one lateral direction with respect to the substrate surface and to thereby simultaneously measure a number of measurement structures disposed laterally offset in relation to one another.

What is claimed is: 
     
       1. A tool, comprising:
 a measuring apparatus configured to determine a relative position of measurement structures relative to each other in a lateral direction, 
 wherein:
 the tool is a microlithography projection exposure tool configured to image mask structures of a first substrate onto a second substrate which is different from the first substrate; 
 the measurement structures are disposed on a surface of the first substrate, or the measurement structures are disposed on a surface of the second substrate; and 
 the measuring apparatus is configured so that, during use of the measuring apparatus:
 the measuring apparatus sends measuring light to a diffractive optical element which splits the measuring light into at least two measuring beams with different propagation directions; 
 the at least two measuring beams run back to the diffractive optical element which combines the at least two measuring beams into a combined beam; and 
 the measuring apparatus simultaneously measures the measurement structures which are laterally offset relative to each other based on the combined beam. 
 
 
 
     
     
       2. The tool of  claim 1 , wherein the measuring apparatus is configured to simultaneously measure the lateral relative position of measurement structures distributed over the whole substrate surface having the measurement structures. 
     
     
       3. The tool of  claim 1 , wherein the measuring structures are on the surface of the second substrate. 
     
     
       4. The tool of  claim 1 , wherein the measuring apparatus comprises an interferometric measuring apparatus. 
     
     
       5. The tool of  claim 1 , wherein:
 the diffractive optical element is the measurement structures which split the measuring light into the at least two measuring beams by diffraction during use of the measuring apparatus; and 
 the measuring apparatus comprises at least two reflective elements configured to reflect the at least two beams to run back onto the measurement structures. 
 
     
     
       6. The tool of  claim 1 , wherein the measuring apparatus comprises the diffractive optical element configured to split the measuring light into the at least two measuring beams with different propagation directions before striking the measurement structures. 
     
     
       7. The tool of  claim 6 , wherein the diffractive optical element comprises a diffraction grating. 
     
     
       8. The tool of  claim 6 , wherein the measuring apparatus is configured to irradiate the measuring light at an angle to the substrate surface to be measured onto the diffractive optical element. 
     
     
       9. The tool of  claim 6 , wherein the measuring apparatus is configured to superimpose coherently images of the measurement structures generated via the at least two measuring beams. 
     
     
       10. The tool of  claim 1 , wherein the measuring apparatus is configured to determine distortion over the substrate surface from the lateral position measurements, and the projection exposure tool further comprises an exposure control device which is configured to adapt a local imaging scale dynamically to the distortion when exposing the substrate. 
     
     
       11. The tool of  claim 1 , wherein the measuring apparatus is configured to take topography measurements at a number of points of the substrate surface simultaneously. 
     
     
       12. The tool of  claim 1 , wherein the measuring apparatus is configured to take the lateral position measurements with the measuring light of a first wavelength, and the topography measurements with another measuring light of a second wavelength. 
     
     
       13. The tool of  claim 12 , wherein the measuring apparatus comprises the diffractive optical element which includes a diffraction grating configured to split the measuring light of the first wavelength into the at least two measuring beams, and the diffraction grating being configured so that at least 90% of the another measuring light of the second wavelength passes through the diffraction grating without being diffracted. 
     
     
       14. The tool of  claim 13 , wherein the diffraction grating is tilted relative to the propagation direction of the another measuring light of the second wavelength. 
     
     
       15. The tool of  claim 1 , wherein the measuring apparatus is configured to take the measurement of the whole substrate surface in less than  10  seconds. 
     
     
       16. A method, comprising:
 directing measuring light toward a diffractive optical element which splits the measuring light into at least two measuring beams; 
 directing the at least two measuring beams back toward the diffractive optical element which combines the at least two measuring beams into a combined beam; 
 determining a relative position of measurement structures in a lateral direction with respect to a substrate on which the measurement structures are disposed by simultaneously measuring the measurement structures which are laterally offset relative to each other based on the combined beam, the substrate being a first substrate or a second substrate; and 
 using a microlithography projection exposure tool to image mask structures on the first substrate onto the second substrate while simultaneously locally varying an imaging parameter based on the lateral position measurements. 
 
     
     
       17. The method of  claim 16 , comprising locally varying an imaging scale while exposing the substrate. 
     
     
       18. The method of  claim 16 , wherein the measurement structures disposed on the substrate comprise diffraction gratings of different periodicities. 
     
     
       19. The method of  claim 16 , wherein the measurement marks are on the second substrate, and an entirety of the measurement structures forms a web structure with a plurality of web meshes which surround structurable product areas with a single exposure of the first substrate. 
     
     
       20. A method, comprising:
 directing measuring light toward a diffractive optical element which splits the measuring light into at least two measuring beams; 
 directing the at least two measuring beams back toward the diffractive optical element which combines the at least two measuring beams into a combined beam; 
 determining a relative position of measurement structures relative to each other in a lateral direction with respect to a substrate on which the measurement structures are disposed by simultaneously interferometrically measuring the measurement structures which are laterally offset relative to each other based on the combined beam. 
 
     
     
       21. A tool, comprising:
 a measuring apparatus configured to determine a relative position of measurement structures relative to each other in a lateral direction, 
 wherein:
 the tool is a microlithography projection exposure tool configured to image mask structures of a first substrate onto a second substrate which is different from the first substrate; 
 the measurement structures are disposed on a surface of the first substrate, or the measurement structures are disposed on a surface of the second substrate; 
 the measuring apparatus comprises a beam splitter configured to split measuring light into at least two measuring beams with different propagation directions before each of the at least two measuring beams strike the measurement structures; and 
 the measuring apparatus is configured so that, during use of the measuring apparatus, the measuring apparatus simultaneously measures the measurement structures which are laterally offset relative to each other. 
 
 
     
     
       22. A tool, comprising:
 a measuring apparatus configured to determine a position of measurement structures relative to each other in a lateral direction, 
 wherein:
 the tool is a microlithography projection exposure tool configured to image mask structures of a first substrate onto a second substrate which is different from the first substrate; 
 the measurement structures are disposed on a surface of the first substrate, or the measurement structures are disposed on a surface of the second substrate; and 
 the measuring apparatus is configured so that, during use of the measuring apparatus:
 a) the measuring apparatus sends measuring light to a beam splitter which splits the measuring light into at least two measuring beams with different propagation directions; 
 b) after a), the at least two measuring beams impinge on the measurement structures; 
 c) after b) the at least two measuring beams run back to the beam splitter; 
 d) after c), the beam splitter combines the at least two measuring beams into a combined beam; and 
 e) after d), the measuring apparatus measures the position of the measurement structures relative to each other in the lateral direction.